The Retrotec workshop in East Sussex, England has been working to rebuild an original Airco DH.9 recovered in India. The aircraft is being restored to an airworthy standard and will be powered by what is reportedly the only airworthy Siddeley Puma engine in the world.
The team recently ran the engine for the second time, and filmed the results. Click the link below to hear the sounds of this exceedingly rare engine.
(via Aero Vintage Spares)